//
//  MainScanPlusButton.swift
//  suixinkan
//

import CYLTabBarController
import UIKit

@MainActor
@objcMembers
/// 主 TabBar 中间扫码核销按钮，基于 CYLTabBarController 的 PlusButton 机制实现。
final class MainScanPlusButton: CYLPlusButton, CYLPlusButtonSubclassing {

    /// 点击扫码按钮时的回调，由 `MainTabBarController` 注入。
    static var onScanTap: (() -> Void)?

    /// 构建中间扫码按钮实例，供 CYLTabBarController 注册使用。
    static func plusButton() -> Any {
        let button = MainScanPlusButton()
        button.setImage(UIImage(named: "icon_scan"), for: .normal)
        button.titleLabel?.textAlignment = .center

        button.titleLabel?.font = UIFont.systemFont(ofSize: 10)
        
        button.setTitle("发布", for: .normal)
        button.setTitleColor(UIColor.gray, for: .normal)
        
        button.setTitle("选中", for: .selected)
        button.setTitleColor(UIColor(red:255.0/255.0,green:102.0/255.0,blue:0,alpha:1.0), for: .selected)
        
        button.adjustsImageWhenHighlighted = false
        button.sizeToFit()
        return button
    }

    /// 指定扫码按钮在 TabBar 中的视觉槽位（位于订单与数据之间）。
    static func indexOfPlusButtonInTabBar() -> UInt {
        2
    }

    /// 调整扫码按钮垂直位置，使其略微凸出 TabBar 顶部。
    static func constantOfPlusButtonCenterYOffset(forTabBarHeight tabBarHeight: CGFloat) -> CGFloat {
        -6
    }

    /// 配置圆形背景与扫码图标，对齐参考工程 CustomMainTabBarCenterAction。
    private func configureAppearance() {
        backgroundColor = .clear

        let circleSize: CGFloat = 58
        let circleView = UIView()
        circleView.isUserInteractionEnabled = false
        circleView.backgroundColor = AppDesign.primary
        circleView.layer.cornerRadius = circleSize / 2
        addSubview(circleView)

        let symbolConfig = UIImage.SymbolConfiguration(pointSize: 30, weight: .bold)
        let iconView = UIImageView(
            image: UIImage(named: "icon_scan")
        )
        iconView.tintColor = .white
        iconView.contentMode = .scaleAspectFit
        iconView.isUserInteractionEnabled = false
        addSubview(iconView)

        circleView.translatesAutoresizingMaskIntoConstraints = false
        iconView.translatesAutoresizingMaskIntoConstraints = false
        NSLayoutConstraint.activate([
            circleView.centerXAnchor.constraint(equalTo: centerXAnchor),
            circleView.centerYAnchor.constraint(equalTo: centerYAnchor),
            circleView.widthAnchor.constraint(equalToConstant: circleSize),
            circleView.heightAnchor.constraint(equalToConstant: circleSize),
            iconView.centerXAnchor.constraint(equalTo: circleView.centerXAnchor),
            iconView.centerYAnchor.constraint(equalTo: circleView.centerYAnchor),
            iconView.widthAnchor.constraint(equalToConstant: 30),
            iconView.heightAnchor.constraint(equalToConstant: 30)
        ])

        accessibilityLabel = "扫码核销"
        accessibilityIdentifier = "main.scan"
    }

    /// 响应用户点击，触发全局扫码流程。
    @objc private func handleScanTap() {
        Self.onScanTap?()
    }
}